package geektime.concurrent;

public class BadLockOnInteger implements Runnable {
    public static Integer i = 0;
    public static BadLockOnInteger instance = new BadLockOnInteger();
 
    @Override
    public void run() {
        for (int j = 0; j < 500000; j++) {
            synchronized (i){ //instance
                i++;
            }
        }
    }
 
    public static void main(String[] args) throws InterruptedException {
        Thread t1 = new Thread(instance);
        Thread t2 = new Thread(instance);
 
        t1.start();
        t2.start();
        t1.join();
        t2.join();
        System.out.println(i);
    }
}
